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Want to Triple Highway Capacity? Put Robot Cars on the Road

A new study on the potential benefits of autonomous cars concludes that "platooning" self-driving vehicles could increase highway efficiency by 273 percent, reports Devin Coldewey.

A paper being presented this week at an Institute of Electrical and Electronics
Engineers (IEEE) conference on vehicular technology concludes that "by banding together into groups, driving much closer to one another than
humans do, and working out the best possible solution to things like
merging and changes in traffic," self-driving cars could dramatically increase the efficiency of the nation's highways. Other recent research supports the conclusions of the paper's author, Patcharinee Tientrakool of Columbia University.

"However far off it may be, transit officials are probably impatient for
that day," writes Coldewey. "Doubling or tripling the capacity of the highways without
spending billions on new lanes and other considerations is a city
planner's dream - to say nothing of the commuters, whose trip to work
would be shorter, safer, and easier."

Robot cars will worsen our addiction to cars, sprawl and oil.

Robot cars will do nothing to alleviate the economic, environmental and human costs of our addiction to cars, sprawl and oil.

If you want your corny old 1950s robot car and your boring, mostly-white suburbs, you'd better be prepared to pay for all the freeways and oil wars they'll require, yourself, and not rely on urban dwellers and non-motorists to do so.

Better technology can make better transportation

The implied accusation of racism was way out of bounds, and does nothing to promote a healthy discussion about planning.

The rejection of this type of automated technology seems very knee-jerk. It can yield environmental and safety benefits, and may be supportive of transit.

And the comment about needing to build more freeways is inexplicable in response to an article about being able to fit so many additional vehicles into existing capacity.

The concern that automated cars could discourage conversion to transit may have some merit. However, there will continue to be some residential locations (rural, very small towns, etc.) where a transit system would not be feasible. Others will continue to see significant benefits of using cars for some trips that could never be efficiently served by transit, even if they rely on transit as their primary means of transportation. Improving the fuel efficiency and safety of all those trips, and reducing the amount of land required for the infrastructure, has very clear environmental benefits.

Additionally, this technology would also create some very obvious benefits in any location that has heavy traffic on a rubber tire transit corridor. Beyond that, if you really try to think creatively, this provides a new avenue to feed people into the transit system more even more efficiently. Individuals in an automated vehicle arriving from a distant location outside the transit system could be synchronized with the transit vehicles so passengers could make a more seamless transfer from their private vehicle to the transit system on the outskirts of the metro area.

It really doesn't take much imagination to see an extension of a Zipcar type business model that would allow ever-increasing numbers of people to give up their personal vehicles, while retaining access to vehicles they can use for more sporadic, specialized trips that are less well served with the traditional, high-capacity mass transit options. Moreover, pricing will help to discourage over-reliance while still meeting these needs.

Implied racism of suburbs

Who said anything about racism, urbanresidue? I merely pointed out that suburbs have, historically, been all-white and that newer ones continue to cater largely to affluent whites. But since you mentioned it, the suburbs have always been about racism. It used to be called “white flight,” remember? The fact that some people of color live in the suburbs does not change anything. The suburbs are not, and never will be, fully racially integrated as long as the suburban and automotive bias in our society continues to sap precious dollars and energy away from making truly sustainable, prosperous, integrated and centralized cities.

That said, robot cars will not exist merely to ease traffic congestion, but will necessarily require, like their non-robotic counterparts, ever-expanding and costly road networks, especially if this horrific idea becomes popular.

As for those who choose to live a rural and/or suburban lifestyle, the reality is that if they want to participate in and benefit from a modern economy, with access to jobs, education, entertainment and transit, then maybe they should move a little closer to an urban center, where they won’t have to rely so heavily on road and other infrastructure subsidies from those who already live in an urban area.

Positive discussion and positive directions with technology

No ifs, ands, or buts; you clearly attributed a motive of racism where none existed. It was an unwarranted attack that was not based on any substance, no matter how you might try to disavow the statement now.

I expect better from somebody who wants to improve the quality of our planning, and I wish you would apologize for that underserved attack. Please try to be positive and constructive in discussions!

Now, if you are interested in substance, perhaps you should reconsider your assumption that automated cars would require an "ever-expanding and costly road network." Again, they are so much more efficient that it would be possible to expand usage greatly without requiring additional capacity. As indicated in previous comments, they may actually help connect more people into transit rather than just expanding auto usage. Your statement simply does not make sense, regardless of whether you think automated cars will increase or decrease auto usage... no matter how many times you make that assertion without explanation.

Of course, you carefully choose to ignore any and every possibility for this technology to improve transit. This technology would allow buses to have absolute priority treatment in every setting. It would improve connections between autos, where they may work better, and transit, keeping more traffic out of the hearts of our cities. Why are you glossing over these portions of the discussion?

Finally, I hope you just didn't think through the suggestion that every farmer should just move closer to town or forgo all modern life. But if that is what you meant, then shame on you for being so thoughtless in your attitude about the people who supply the food that sustains you.

No more Mr. Nice Guy

As for keeping the discussion "positive and contructive," maybe I don't feel like playing Mr. Nice Guy anymore, given the attacks that right wing nut job Tea Party opponents of Smart Growth have been conducting against the rest of us lately.

Maybe it's high time urbanists, planners and liberals grew a set and fought fire with fire.

Rural American farmers, meanwhile, who also tend to be white conservatives enjoying generous taxpayer subsidies, can certainly stay where they are, but not on my dime. Not anymore.

Lastly, only someone deeply in denial---or a shill for the auto and oil industries---thinks that self-driving cars are a transportation solution and one that will dovetail with urbanism, sustainable growth and efficient use of public dollars.

Self-driving cars and th' fyoocher.

Robot cars will do nothing to alleviate the economic, environmental and human costs of our addiction to cars, sprawl and oil.

Calm down cowboy. You don't know whether this is true. Unless you can see into the future (which may be possible, judging from the certitude in your reply). If that is true, what are the winning PowerBall numbers for Saturday, buddy ol' pal of mine?

Best,

D

Let's put the "smart" in smart growth together

If you believe that this technology would have such negative effects, can you please try to address the points that have already been raised, and explain HOW the negative effects you are asserting would operationalize themselves?

Just to reassure you, nobody is attacking you by asking you to remain focused on substantive planning issues, rather than attributing racial motives to people who expressed none.

Nor is anybody attacking you by expressing a different view than your own about the potential uses and outcomes of new technology. Last time I checked, "smart" was the key ingredient in smart growth, so we should be open to exploring ways that smart technologies can contribute.

Danger of Tripling Highway Capacity

The danger is obvious. In the past, when freeways have been built or expanded, automobile travel has generally increased to fill the increased capacity.

It is called "induced demand," folks.

All else being equal, increasing highway capacity and speed by using robot-cars will induce demand, just as freeway expansion has.

Robot cars could make transportation more efficient without inducing demand, if we:
-- had strict urban growth boundaries, so they do not induce sprawl
-- had a VMT tax high enough to keep VMT from increasing.

These points seem very obvious to me, and I am surprised to see so much disagreement about them on planetizen.

PS: About the author, I see: "Devin Coldewey is a contributing writer for NBC News Digital." I expect he doesn't have much background in city planning; anyone who is familiar with the history of freeway expansion would not say so glibly that "Doubling or tripling the capacity of the highways without spending billions on new lanes and other considerations is a city planner's dream."

Me and Robot Cars

Dano, note that I did not say I am against robot cars. I just said that there is a danger that the increased capacity will induce demand, which we need to deal with.

I believe that Jonathan Nettler was thinking of exactly this point about increased capacity inducing demand when he gave the story the heading "Want to Triple Highway Capacity?" He could have used the heading "Want Safe, Convenient Commutes" - but instead he used a headline meant to call attention to the problems that increased freeway capacity has caused in the past.

This sort of platooning of robot cars will not happen for a long time. I suspect that Google is designing robot cars to call everyone's attention to a technology that will be used in industrial applications long before it becomes widespread among cars. I can see it used soon in places like Amazon.com's warehouses.

One problem with the discussion here (and with the article) is that everyone seems to assume that the technology will either be developed for commuters' cars or will not be developed at all. In fact, it will be developed for other applications, whether city planners like it or not. Then, at some point in not very near future, it will be also become common enough among cars that city planners will have to figure out a way to deal with it.

Charles Siegel

Induced demand is not infinite demand

Induced demand is not infinite demand. Let's not pretend that people necessarily keep driving just because there is a road there to drive on. History is not destiny, either. So let's carefully consider the actual dynamics at work and imagine how we can influence the future.

Induced demand results from an increase in consumption when prices drop. How much do you actually expect automated cars to reduce the real costs? Some as a result of less congestion, ok. Some as a result of better fuel efficiency, ok. It would be reasonable to assume that people would experience reduced costs for their time when relieved of the need to drive, so we can add that to the list too. So yes, there is a tidy list of lower costs that could increase consumption by some level.

Yet there are countervailing pressures that should also be considered. Fuel costs are likely to continue to increase. Younger drivers are showing less interest in owning cars as a status symbol, and the higher initial and maintenance costs for these vehicles may make Zipcar-type models more likely. That would result in higher costs per trip, as well as a better internalization of the cost of each trip. Moreover, the opportunity to give up the need to park all those cars at your home opens up your real estate for better uses - a bedroom for your aging mother-in-law, a front deck to grill with your friends, etc.

And, as the anti-car crowd seems intent on ignoring, these technologies can and almost certainly will also make transit more effective and thus somewhat more competitive (or at least reduce the loss of competitiveness from the improved auto option).

Put together, it seems very, very, unlikely that demand in an already auto-saturated market, you're going to see a tripling of auto trip-making. If you think that outcome makes sense, could you please explain how you think the elasticities would support such an outcome?

With so many cars already dominating virtually every neighborhood around the country, this sort of technology seems like an positive way to increase efficiency and transition to more effective, sustainable transportation models that meets needs with less cost and impacts.

If you like it or not, there will be a market for these vehicles. Let's find a way to make the most of them, instead of losing the opportunity to shape their introduction into a movement for improved outcomes.

Misunderstanding of Induced Demand

"Induced demand results from an increase in consumption when prices drop."

That is not what the term means in general is certainly not how the term in used in transportation planning.

"Induced demand, or latent demand, is the phenomenon that after supply increases, more of a good is consumed. This is entirely consistent with the economic theory of supply and demand; however, this idea has become important in the debate over the expansion of transportation systems, and is often used as an argument against widening roads, such as major commuter roads."http://en.wikipedia.org/wiki/Induced_demand

"Put together, it seems very, very, unlikely that demand in an already auto-saturated market, you're going to see a tripling of auto trip-making."

Right, if I say that there is induced demand, I must mean that tripling capacity will triple demand. Great example of the straw-man fallacy.

Judging from the two quotes from you that I include here, you do not have any clear idea of what you yourself mean by induced demand. In the first quote, you say it is a reaction to price. But if it is a reaction to price, then there is no reason to expect that a tripling of freeway capacity will lead to a tripling of driving, as you say in the second quote.

I know you usually prolong arguments endlessly, and we can all see how illogical and ill informed you are in this case, so I am not going to reply to your inevitable, long-winded response.

Economics 101 on Induced Demand

The only logical error appears to be in your application of the definition you quoted.

Let's carefully examine the quote that you found to define "induced demand." (It is not technically accurate, more on that below, but it is a reasonable working definition):

"Induced demand, or latent demand, is the phenomenon that after supply increases, more of a good is consumed."

Step back to the most basic, fundamental level of economics: price is the point where supply equals demand. When supply increases, that point of intersection yields a lower price. Therefore, the logical application of the definition you provide:
Supply increases --> price decreases --> consumption increases.

That is precisely what I wrote:
"Induced demand results from an increase in consumption when prices drop."

Now, I will maintain that the definition you looked up was incomplete, since there are other ways to induce demand besides increasing supply. If you had a toll road, for example, decreasing the toll rate could induce demand. So the definition you provided explains some cases of induced demand, but is not as complete or accurate as the definition I provided. At any rate, there is no logical case you can make that my statement was in any way incorrect.

I will admit I may have been a little sloppy on explaining the statement about tripling auto trip-making, but there is no "straw-man fallacy" there. Allow me to try to clarify how it was a logical, reasonable response to your argument and the prior arguments I believed you were supporting.

You made a statement that induced demand resulted in traffic "generally increased to fill the increased capacity." It is not entirely clear what conclusion you were drawing, but it seems reasonable to assume you meant that traffic would fill the increased capacity in this case. If that is not correct, perhaps you can clarify?

Additionally, you seemed to be supporting the contentions of baycityroller1, who argues that this technology would result in increased highway construction.

So it appeared you were arguing that the full capacity would be filled, if not more. If the capacity tripled, that would in fact require the tripling of trip-making, as I mentioned.

There is no logical error in anything I wrote. If there was a misunderstanding of your argument about how traffic would "fill the increased capacity," perhaps you can make it more clear?

I am sorry if you find this "long-winded," but it was your own error that initiated this tangent.

Now, perhaps, you can finally address the relationship with, and potential to support, transit? Or was this all just a diversion to distract attention?

Economics 101 Revisited

In Economics 101, you learn that there is a difference between:
-- A change in price that leads to a greater quantity being purchased without any change in the demand curve.
-- A change that shifts the entire demand curve upward, so more is purchased at any given price.

Induced demand is the second of these. It does not operate by lowering price.

Think about freeway expansions: they do not lower the cost of driving, but they do generate more driving.

Sorry to break my resolution not to respond. I am obviously wasting my time repeating an obvious point of elementary economics.

Please check your text book, thanks

The demand curve absolutely and unequivocally does not change. You will not find any support for that contention anywhere.

There is no underlying change in people's desire to take a trip somewhere. They are more likely to act on the desire they already have when it becomes easier.

The definition you yourself provided clearly contradicts this contention of yours. Let's look at it again:
"Induced demand, or latent demand, is the phenomenon that after supply increases, more of a good is consumed."

It does NOT say, suggest, or in any other way indicate that the demand curve increases. It clearly indicates that increasing supply results in increased consumption - that happens because the intersection of the NEW supply curve and the EXISTING demand curve is at a lower price point with a higher quantity.

So please revisit your economics textbook. If you think you find something that indicates a change in the demand function, please let us know.

Stop dwelling on the past and find ways to leverage technology

Nobody is disputing the historic effects of sprawl. However, you appear to be confusing and overlooking much more complex economic and sociodemographic dynamics.

Since we are unable to have a conversation at the most basic economic level, it would be fruitless for me to try to delve into the issues of multiple substitution effects, the effects of increased budgets, the contributions of subsidies on complementary goods (suburban housing) or any of the other complexities that resulted in our historic patterns.

It is completely wrong, however, to suggest that these economic theories are stuck in the past. These are precisely the very tools we use to advocate and implement congestion pricing and other progressive planning improvements. (Besides, it seems a bit inappropriate to reference specific concepts based on microeconomic theory, and then call the whole field outdated when it turns out you were not using the concept properly...)

I'm not stuck dwelling on the past. Let me repeat: history is not destiny. If we can define productive uses for technologies that are likely to be adopted, we can craft a more positive future.

What Is The Main Issue?

I think that the main issue is that America's per capita VMT is twice as much as it was in 1960, and that the excessive amount of driving provides no benefit to the average person but is a huge economic burden to the average person and has huge environmental costs.

You and I seem to have fundamentally different goals:

-- You apparently think it is good to increase per capita VMT (which is what induced demand does) as long as we also increase transit use.

-- I, like most urbanists today, believe we should reduce the need for transportation by building more compact walkable cities.

That is the main issue.

(Note that you are the one who introduced the distraction from this main issue by making a point about induced demand and pricing that shows you do not understand a basic point of elementary economics.)

Charles Siegel

More efficient transportation for better communities

THE POINT: Better technology could - if we as planners provide a productive vision of the future to integrate it productively - decrease fuel consumption, reduce lost time, create economic savings, and free up land currently used for parking for more productive uses.

I already made all those points... which you somehow ignored or miconstrued into an agenda to increase VMT?

I think it might have helped if you had taken the time to try reading it instead of jumping to wild conclusions about my motives.

(I would note, in addition, that VMT is really useful only as a proxy for the issues of emissions, fuel usage/resource depletion, congestion, public safety, and sprawl. If new technology could loosen those correlations by improving emissions and fuel efficiency, optimizing traffic flow and safety, and allowing for land to be reclaimed from cars in our cities, then it would be less meaningful. We always need to be careful to focus on the ends and not the means - reducing VMT is ultimately a means to the ends of more livable communities.)

All that glitters is not gold

No, urbanresidue and Dano, I’m not going to sit here and explain any further how these so-called robot cars, as well as the roads and oil wars they will require, will only hinder attempts to fix our cities and our world. It’s a no-brainer. We need to revitalize our urban cores, limit suburban sprawl, make efficient use of public dollars, heal the environment, encourage geopolitical stability, improve mass transit, balance transit spending and develop clean, sustainable energy sources. Self-driving cars will not advance any of the goals.

Why don’t you explain how they will?

Unless, of course, you don’t think those are worthy goals.

The bottom line is this: public transportation has a hard enough time as it is competing with private transportation, without people believing that what glitters is gold and embracing the concept of self-driving cars as a transportation solution. I have the same issue with electric cars, which also do nothing to mitigate the effects of sprawl and exponentially-costly, budget-busting road spending, to the tune of some several hundred billion dollars a year! In many cities, public transportation spending is being drastically cut, while plans for high speed rail are being vigorously challenged as we speak. The roads that regular, self-driving or electric cars will be driven upon face no such cuts and not nearly enough opposition from those who see the folly of America’s sick love affair with the car and suburbia.

All the money and energy that is being put into self-driving cars would be better spent on improving and expanding public transportation, which will also go a long way towards achieving those other goals mentioned above.

Is Transit What Matters to You?

Looking at your comments over the years, it is obvious that your main interest throughout is increasing automobile speeds and increasing or maintaining automobile capacity.

You come up with other excuses in each thread, but the excuses are mutually contradictory. For example, you say you are in favor of one-way rather than two-way traffic streets to make it possible to reclaim space for pedestrians, as at Madison Square. But you are not in favor of removing the Sheridan Expressway, which would reclaim much more space for pedestrians.

The constant is that both one-way streets and freeways increase automobile speeds and capacity – as do robot cars. Your excuses vary - safety, pedestrian space, support for transit, or whatever - and the only constant throughout is automobile speed and capacity. Well, there is one other constant: you are always on the opposite side from environmentalists.

You gave yourself away in this thread, when you said that the expansion of American freeways since World War II did not create new demand; it just accommodated demand that was already there. You think the increased VMT and sprawl during that period are good things, because they are what people want.

(Apparently, you do not know the literal meaning of the words “induced” and “latent.” “Induced demand” means demand that would not have been there if the roads had not been built. It is different from “latent demand,” which means demand that was always there but was not satisfied.)

Of course, you have a right to your opinion. If you think that our high level of VMT is a good thing, that is your right. But you could have more honest discussions if you focused on the fact that you want to accommodate this automobile-centered way of life, rather than arguing that you are mainly interested in the benefits to transit, the benefits to pedestrians, the benefits to safety, or whatever your current excuse is.

Incidentally, I think it is interesting that you also defend modernist architecture. It is more evidence for my belief that esthetic modernism often works against political progressivism.

When I talk about transitioning from existing conditions to a more efficient, complete transportation system that is flexible, sustainable, non-polluting, supportive of urban land uses, and accommodates various travel needs, I speak from both life and work experience.

p.p.s
Final word on why asphalt does not result in the spontaneous generation of automobiles or deprive people of their freewill.

If you want to take other causal factors like housing subsidies, budget increases due to post-war prosperity, etc. and try to lump them into a magical "induced demand" (which admittedly has always been a bit of a misnomer that probably invites some confusion), that's your choice. But I do not prescribe to the use of specific analytical terms as squishy, undefinable rhetoric for political agendas.

Roadways in and of themselves will never cause more demand for trips, they merely allow the trips that people want to make, either by diverting from modes that have become less attractive or by going places that were otherwise too difficult. That includes moving to the suburbs and driving back and forth. People wanted to move to the suburbs, but didn't do it previously because the transportation cost was too high. They did not move to the suburbs because what they wanted was the drive on the highway. (Disclaimer - do not continue to misrepresent these statements as claims that the prices that informed the choices individuals made were not skewed by a whole range of bad policies. They were... but that all operates separately from the specific question of induced demand.)

Again, other factors like housing subsidies, redlining urban neighborhoods, taxing railroads, etc. all had an effect - but those are not demand induced by the highway, and should be accounted for separately. Highway construction and the other policies certainly formed comprehensive total packages, but they still operated through different dynamics that each had a role that should be disaggregated to improve our understanding of how things actually work. You will not find any credible increase in driving that was not due to the decrease in the cost of driving, or due to a separate factor that could be identified like budget increases, etc.

N.B.
I still have seen no substantive argument, that would demonstrate that automated vehicle technology should be rejected because of necessarily disastrous outcomes for our metropolitan areas. The suggestion of VMT increases assumed no beneficial use of the technology by or in support of transit, did not allow for any conversion of urban land from parking to more beneficial uses resulting in more efficient, denser cities, nor did it take into consideration any of the cost issues that have been raised. It appears the only way to support the harsh indictment against automated vehicle technology is to assume the worst in terms of impacts and entirely dismiss any positive effects.

What is tragic is that we cannot have a productive exchange about what uses of this whole technology would benefit cities, and what other specific uses could be detrimental, and how those uses might be influenced.

Website activity speaks for itself

Consider the size of the planning community and the great interest in these topics, why is it that almost nobody participates in discussion on this website?

Perhaps it is because we have better things to do than respond to baseless personal attacks that deliberately distract from the issues we really want to discuss as planners. There are clear differences between standard website moderation practices that ensure everyone has a right to engage in productive discussions, and censorship, but why should the misrepresentations end now?

Fine, you "win." You can monopolize a dead discussion board with all the personal animosities you want. Like everyone else who was apparently a little quicker to give up than me, I have more productive things to do - like improving the quality of our communities.